What is asthma?

Asthma is a common condition that affects the airways. The airways are tubes that direct air into the lungs. In asthma, the airways become inflamed. This process may be due in part to the body’s immune system developing what is termed an "allergic response". Inflammation makes the airways highly sensitive to a number of triggers.

An asthma attack occurs when the airways narrow in response to one of these triggers. Although the first symptoms of asthma can occur at any age, recurrent episodes of wheezing occur before the age of 6 years in most patients with asthma. This suggests that asthma, at any age, is likely to originate in childhood or earlier. [2] If present during mid to late childhood, asthma can become a life-long condition.

There have been some new asthma trends in recent times: [2]
  • Rates of asthma are increasing worldwide
  • Asthma is generally more common in western countries and less common in developing countries
  • Asthma is more prevalent in English-speaking countries
  • Asthma is becoming more common in developing countries as they become more westernized or communities become urbanized.